A St. Paul nurse, labor leader and legislator looking to ride the 2018 wave that’s propelling progressive women to power, but who’s not as well known as her competitors.

The 12-year state attorney general and an accomplished trial lawyer, but a more private politician now looking to lead Minnesota.

A teacher-soldier-congressman from Mankato who thinks he can win you over but whose progressive bona fides are being challenged.

Erin Murphy, Lori Swanson and Tim Walz, respectively, are locked in a three-way battle for the DFL nomination for governor. All three hope to emerge from the Aug. 14 primary, stitch together a divided party and beat the Republican candidate. The consequences are huge: Whether Minnesota stays on a path set by eight years of a Democratic governor, or joins neighboring states in choosing Republican rule.

“The stakes are enormous,” said Jeff Blodgett, a longtime DFL operative not involved in any of the campaigns. The next governor will be in office during the redistricting of the state’s congressional and legislative districts. “This election will help determine the shape of politics for the next decade in Minnesota, and that’s not hyperbole,” he said.

In their own way, each DFL candidate is contending with the forces that have pushed the upper Great Lakes states toward Republicans, and Minnesota to the brink of GOP hegemony after big DFL losses in 2016.

Murphy, the DFL-endorsed candidate and a six-term state representative from St. Paul, is working to energize young voters. A nurse by training, she is pushing health care changes that would pave the way for “single payer,” or government-run health insurance. Having picked a 32-year-old running mate in state Rep. Erin Maye Quade of Apple Valley, Murphy is hoping strong connections to a new generation of ardent DFL activists will drive up support in the population-rich, increasingly diverse metro.

“I feel like I’ve had the best seat in the house in the past two years of our politics, as I watch Minnesotans grab ... the reins of our democracy and take us in a different direction,” Murphy, 58, said in a recent interview.

Walz, a U.S. congressman from southern Minnesota since 2006, starts with a compelling biography. He rose to command sergeant major in the National Guard, the highest ranked enlisted soldier to ever serve in Congress. He spent 20 years as a high school teacher and coach, and for a decade in Congress he advanced progressive goals from a Republican-leaning district.

Walz, 54, thinks greater Minnesota voters who left the DFL in droves in 2014 and 2016 can be brought back by a candidate from outside the Twin Cities, a focus on education — and his obsessive dedication to closing the deal.

“If there’s 100 people in the room and 99 are with me, and one isn’t, I’ll talk to the one for a really long time,” Walz said recently. “I really want to know why are you dissatisfied.”

Swanson, 51, jumped into the race late, in June, and is banking on an older model of politics. The attorney general since 2007, her three statewide wins mean she’s well-known to voters — mostly through suing companies accused of malfeasance. Her campaign strategy relies on years of trust she’s tried to build with Minnesotans, with less deference to recent ideological trends on the left.

Her focus: pragmatism and results.

“We’re about getting things done and moving the state forward,” Swanson told a gathering at Cirrus Aircraft in Duluth.

She ticked off a range of issues left undone by the Legislature this year, including aligning the state tax code with the new federal tax rules, and confronting the opioid crisis. It was a subtle rebuke of DFL Gov. Mark Dayton, who endorsed Murphy.

“My record and background are as a practical problem-solver for the betterment of the public,” Swanson said in a later interview, citing the recent $850 million settlement with 3M over contaminated drinking water.

Swanson’s lawyerly demeanor is a bit at odds with the gregarious style that candidates for governor typically adopt. While touring the Cirrus plant, she walked up to engineers and introduced herself: “Hi, I’m Lori Swanson” — neglecting to mention that she is the attorney general and is running for governor.

Later, in a neighborhood up the hill from Lake Superior, Swanson stood on ground that was once home to her paternal grandparents. In front of photos of her family, she described their Depression-era life of penury, her mother raised in a home without indoor plumbing or electricity, her father forced to borrow hockey skates.

She described how Minnesota’s education system was their salvation, helping her father earn a degree from the U and become an engineer.

After reading his eighth-grade valedictorian speech — in which he extolled the American virtue of making the seemingly impossible come true — she said, “I’m running for governor because I believe in possibilities.”

Walz, who crafted a moderate persona to appeal to southern Minnesota voters, spent more than a year trying to win over 1,400 DFL activists who gathered at the state convention — a more liberal constituency. He backed away from the National Rifle Association, which previously supported him. He said he regretted a 2015 House vote that would have made it more difficult for people from war-torn countries like Syria to come here. But it was not enough — Murphy won the endorsement.

After the convention, Walz reset his campaign. He recently walked through his old classroom at Mankato West High School.

Walz looked at home at the front of the classroom where he taught geography, his teaching enriched by time in China and his military deployments.

“It’s time for an educator to be governor of Minnesota,” he said.

Colin Green, a former student who is now a father and school district maintenance supervisor, said Walz opened his eyes. “Expansion of consciousness, being aware of the entire world around us,” Green said. “Beginning with listening to the opinions of others and engaging and talking to one another.”

On a drive to New Ulm to inspect flood damage, Walz pointed to the soybean fields, whose farmers are grappling with an escalating trade war.

“These farms have been in these families for 100 years. If you go bankrupt, you’re not just losing your job and you go get another one,” he said. “You’re losing an entire legacy of five generations.”

He critiqued fellow Democrats who see the best path to victory in relying on high voter turnout in the cities and suburbs. “How do you talk to that guy and see about being partners?” Walz said of the farmers.

If the only people voting in the DFL primary were the Minnesotans gathered at the coffee shop and wine bar called the Hideaway in Northfield, Murphy would be cruising to victory.

Clifford Knutson of Lonsdale does not look or sound like a typical DFL voter. “I didn’t grow up with this,” he said of DFL politics. He’s a sportsman who runs a taxidermy business, but he has also been hit with expensive health care, paying $50 to $60 for an asthma inhaler that used to cost $5.

Health care, he said, is his No. 1 issue. “And I will be voting for her,” he said of Murphy.

Later, at a picnic for SEIU health care workers in St. Paul’s Como Park, Murphy belted out her speech: “I was raised in a family that taught me about a powerful kind of politics. The kind of politics that is about us.”

But Murphy also knows that many DFL voters are driven this year by anxiety, and that every hero needs its supervillain.

“We recognize that the powerful interests inside the Capitol, the status quo corporate power of the Capitol — those are the interests that are underfunding our schools, those are the interests denying people health care,” Murphy said. “Those are the interests that are polluting our rivers and lakes. Those are the interests that we will take on together when we win this election.”